System for wet impact plating

ABSTRACT

A system for wet impact plating of metal parts utilizing single tumbling barrel for independent parts rinsing and impacting operations respectively when interchangeable, smaller perforate and imperforate barrel doors are secured to a larger door of the barrel. Rinsing water is supplied to the barrel while rotating with the perforate door in position. Water expenditure is thereby minimized and the rinsing effluent is thereby effectively separated from the impacting medium. A stationary bin with a screen for separating parts from the impacting medium and aqueous solutions is positioned beneath the barrel. Communicating with the bin in selectively operable relationship is a venturi eductor which, together with a pump communicating with a water storage tank, is operable to rapidly transfer the impacting medium to a hopper positioned over the barrel for reuse while generating sufficient turbulence to tend to cleanse the impacting medium of spent plating material and promoter chemicals. These spent materials pass, with overflow water, through an overflow strainer in the hopper to the water storage tank where they settle and are subsequently removed. Substantially all water is thereby recovered and reused, and the frequency of impacting medium rectification is materially lessened. Two separate charges of impacting medium are used in the system, and several tumbling barrel units may be supported by a single water storage tank where the water level and temperature are controlled.

United States Patent [1 1 Coch [ SYSTEM FOR WET IMPACT PLATING [75]Inventor: Lester Coch, Northport, N.Y.

[73] Assignee: Waldes Kohinoor Inc., Long Island City, N.Y.

[22] Filed: May 23, 1972 [21] Appl. No.: 256,191

Related US. Application Data [62] Division of Ser. No. 53,123, July 8,1970, Pat. No.

[52] US. Cl 118/603, 118/418, 209/268 [51] Int. Cl. B05c 3/08 [58] Fieldof Search 118/19, 418, 603,

Primary Examiner--Morris Kaplan AttorneyPeter H. Smolka Dec. 4, 1973[57] ABSTRACT A system for wet impact plating of metal parts utilizingsingle tumbling barrel for independent parts rinsing and impactingoperations respectively when inter changeable, smaller perforate andimperforate barrel doors are secured to a larger door of the barrel.Rinsing water is supplied to the barrel while rotating with theperforate door in position. Water expenditure is thereby minimized andthe rinsing effluent is thereby efi'ectively separated from theimpacting medium. A stationary bin with a screen for separating partsfrom the impacting medium and aqueous solutions is positioned beneaththe barrel. Communicating with the bin in selectively operablerelationship is a venturi eductor which, together with a pumpcommunicating with a water storage tank, is operable to rapidly transferthe impacting medium to a hopper positioned over the barrel for reusewhile generating sufficient turbulence to tend to cleanse the impactingmedium of spent plating material and promoter chemicals. These spentmaterials pass, with overflow water, through an overflow strainer in thehopper to the water storage tank where they settle and are subsequentlyremoved. Substantially all water is thereby recovered and reused, andthe frequency of impacting medium rectification is materially lessened.Two separate charges of impacting medium are used in the system, andseveral tumbling barrel units may be supported by a single water storagetank where the water level and temperature are controlled.

12 Claims, 5 Drawing Figures PATENTEU HEB 4197a SHEET 1 UF 2 HUI I norFIG. 3

SYSTEM FOR WET IMPACT PLATING This is a continuation, division ofapplication Ser. No. 53,123, filed July 8, 1970 and now U. S. Pat. No.3,690,935.

BACKGROUND OF THE INVENTION This invention relates to wet impact platingof metal parts. More particularly, this invention relates to an improvedsystem for wet impact plating of such parts.

It has been common for many years to provide a base metal with a brightand permanently adhered metalliccoating through wet mechanical platingprocesses. Such processes generally involve the utilization of metaldust particles th'atare cold welded to the base metal by impactingagainst its surfaces. An impacting medium placed with theparticles in anagitated container, with or without promoterchemicals to aid in th eplatin process, andjmm'ersed irgaliquid carrier as a pre-treating andplating barrel, the other, a

generally sieve-like unit, functioning as a separating drum. Parts to beplated may be cleansed in the first container or barrel into which achemical solution is placed. The parts are then plated in the samebarrel.

Transfer of the barrel contents to the separating drum is followed byrotation of that drum.

The drum is speciallyconstructed so that rotation in one directiontumbles the load, with liquid and small particles falling throughperforations in the drum. Opposite rotation discharges the parts fromthe drum; Water may be added for cleansing purposes and to aid in theseparation. The entire drum contents passing through the perforationsare collected in a pan and then transferred to the first container, orbarrel, for further use. I

Although such systems may be adequate for some purposes, their use maysometimes prove undesirable for a number of reasons. For example,cleansing and impact plating of the parts in the same solid barrel mayresult in unnecessary attrition of the impacting medium or in the needfor substantial fresh water rinsing and ensuing effluent disposal.During a cleansing operation in the solid barrel, corrosion, scale andcarbon smut, etc. is often removed from the parts to be plated. In theabsence of some special steps taken for complete removal of theseelements from the barrel p'riorto the plating ing rinsing cycles isprovided. Although this chute may permit disposal of the rinsingeffluent prior to plating, the use of substantial fresh water isrequired for rinsing since the rinse water must be spilled or overflowedout of the barrel into the chute.

It would, therefore, be highly desirable to rovide a I wet impactplating system whereinclea'nsing and this ing are accomplished. prior toplating while minimizing the amount of rinse water required and insuringseparation of the rinse water andreffluent from theparts prior toplating. e o

A particularly significant disadvantage of the. prior proposed systeminvolved the reuseof the impacting medium transferred to the-platingbarrel from the pan beneath the separating drum. Since spent platingmaterial and promoter-chemicals are present in the mass of material sotransferred, and since these spent materials become present inincreasing amounts during subsequent cycles, the length of time betweenperiods of needed rectification of the impacting medium may be extremelyshort. Since the quantity of impacting medium utilized is generallydisporoportionally great in relation. to the quantity of parts plated,the requirement of frequent rectification may make commercial platingoperations impractical.

Moreover, even the water utilized in the prior system totransfer theimpacting medium to the barrel for reuse were drained off prior to aplating operation, the spent materials may not be effectively removedand, at any rate, drainage may significantly increase the amount'offresh water utilized.

It would, therefore, be desirable to provide a wet impact plating systemwherein the frequency of impact medium recitification is reduced throughseparation of spent materials therefrom. It would also be desirable toincorporate a water recovery and reuse mechanism in the system so as tominimize fresh water expenditure.

OBJECTS AND SUMMARY OF A PREFERRED EMBODIMENT OF THE INVENTION It is,therefore, a general object of the invention to. provide a system forwet impact plating of metal parts which obviates or minimizesdisadvantages of the sorta' stiz ls ynoted:

It is a particular (Eject of the ifitzririoii to provide a system forwet impact plating of metal parts wherein the frequency of rectificationof the impacting medium is substantially decreased.

It is a related object of the invention to provide such a system whereinefficient separation of spent materials from the impacting medium isinvolved and which may utilize alternately two charges of impactingmedium in order to further decrease the frequency of impacting mediumrectification.

It is a further object of the invention to provide a system for wetimpact plating of metal parts wherein a water recovery and re-usemechanism is employed in the rapid transfer of the impacting medium forreuse while effectively separating the spent material from the impactingmedium, both with virtually minimal fresh water expenditure and disposalof effluent.

It is yet another object of the invention to provide a system for wetimpact plating of metal parts wherein separate and independent partsrinsing and impacting operations are performed in the same containerwith the rinsing operation involving minimal fresh water expenditureand'effluent disposal and insuring efficient separation of therinsewater andv effluent from the parts prior to plating;

A preferred form of the invention intended to accomplish at least someof the foregoing objects comprises a system for wet impact plating ofmetal parts wherein a single tumbling barrel rotatable about a generallyhorizontal axis is utilized for independent parts cleansing, rinsing andimpacting phases of the system operation. A rinsing valve communicateswith means defining an opening in the barrel on the axis of rotation. Aside opening extends longitudinally of the barrel between opposite ends,the barrel being otherwise imperforate. A large, imperforate door havingan access opening is selectively securable to the barrel coextensivelywith the side opening thereof.

Selectively and interchangeably securable to the large, imperforate doorcoextensively with its access opening are a smaller perforate door and asmaller imperforate door. The perforate door is sized to retain themetal parts and the impacting medium utilized in the process whilepermitting aqueous solutions to pass through the perforations in thedoor. The smaller imperforate door, together with the larger imperforatedoor when both are secured in position, entirely blocks the side openingof the barrel.

A stationary bin is positioned beneath the barrel and supports a screenadjacent the bin top. The screen is sized to retain the plated parts andto pass the impacting medium and aqueous solutions. A venturi eductorcommunicates with the bottom of the bin in selectively operablerelationship and a conduit provides communication between the venturieductor and an overhead hopper positioned above the barrel. The bottomof the overhead hopper is provided with a valve selectively operable topermit the hopper contents to fall into the barrel.

In gravity feed communication between the top of the overhead hopper anda water storage tank is an overflow strainer, the strainer blockingpassage of the impacting medium. A pump is provided for pumping waterfrom the water storage tank through the venturi eductor and to theoverhead hopper from which overflow water and suspended spent materialspass to the water storage tank. Several container systems may besupported by a single water storage tank, and the tank water level aswell as its temperature are controlled.

In operation the metal parts to be plated are loaded into the tumblingbarrel through the side opening thereof. The selectively operable valve,or pet cock, of the overhead hopper is opened to permit a charge ofimpacting medium settled at the bottom of the overhead hopper to dropinto the barrel through its side opening. An amount of water in theoverhead hopper, usually enough to cover the charge in the hopper, isalso permitted to pass into the barrel with the impacting medium. Thelarger imperforate door is then secured in position on the barrel acrossits side opening.

Conventional cleansing chemicals are then added to the barrel throughthe access opening in the larger imperforate door. Upon securing of thesmaller imperfor ate door to the larger imperforate door so as to blockits access opening, the barrel is rotated about a generally horizontalaxis for a time period sufficient to cleanse the parts. At the same timethe cleansing chemicals will effect the cleansing of the impactingmedium.

Thereafter the smaller imperforate door is replaced with the perforate.door. Used cleansing chemicals and dirty solution may be rinsed out byopening the rinsing, valve and admitting rinsing water to the barrelduring rotation thereof. Thus a rolling rinse is accomplished withminimum water expenditure. During the time period of the rinsing cycle,the parts the impacting medium are retained in the barrel by theperforate door and the rinsing effluent comprised of the remainingbarrel contents passes through theperforate door, through the screenadjacent the top of the bin'beneath the barrel, and into the bin. 1 l

Removal of the perforate door is followed by the addition of platingmaterials through the access opening 'in the larger imperforate door.Conventional promoter chemicals may also be added at this'time.Afterwards the smaller imperforate door is secured in position acrossthe access opening of the larger imperforate door. i

The barrel is then rotated about the generally horiama a isj naimepsnqssymcism ai way plat the parts through the interaction of theimpacting medium, the plating material and the parts. During thisperiod, water which has been added to the barrel serves as a carrier forthe plating material and as a mass lubricant whereby damage to the partsthrough abrasion and tangling'of the parts is minimized.

Following removal of the larger imperforate door from the tumblingbarrel, the barrel contents are emptied onto the screen adjacent the topof the bin. The screen serves to separate the plated parts from theremaining barrel contents which pass into the bin through the screen.The parts may be hosed down at this time. Since the bin is generallysized to accommodate the volume of a single impacting medium chargeutilized, virtually all of the rinsing effluent previously accumulatedin the bin is displaced out of the bin.

After accumulation of the charge of impacting medium in the bin, wateris pumped from the storage tank through the venturi eductor tohydraulically transfer the bin contents to the overhead hopper. Duringthis time sufficient turbulence is generated so as to tend to cleansethe impacting medium of spent plating material, and promoter chemical ifutilized. Overflow water is drained from the overhead hopper, with thespent material, to the water storage tank through the overflow strainer.The strainer retains the impacting medium in the hopper and theimpacting medium then settles to the hopper bottom.

The spent material which is carried with the overflow water into thestorage tank settles out, by reason of the turbulent free condition inthat tank, and may be manually cleaned from the storage tankperiodically.

In practice, a single storage tank may support a plurality of tumblingbarrel systems, with the water level in the storage tank beingmaintained constant through a float valve. Make-up water suppliedthrough the float valve to the storage tank may be thermostaticallycontrolled to control the temperature of water in the system.

Throughout the operation the need for frequent impacting mediumrectification is further minimized through the use of two impactingmedium charges. One charge is present in the overhead hopper while theother remains in either the tumbling barrel or the bin. Prior totransfer of the one charge from the bin to the overhead hopper, thetumbling barrel is recharged with the impacting medium maintained in thehopper.

Other objects. and advantages of the present invention will becomeapparent with reference to the following detailed description taken inconjunction with the accompanying drawings in which:

THE DRAWINGS sembly shown in FIG. 4, together with a pump utilized 1 todraw water from the tank assembly.

DETAILED DESCRIPTION Detailed Structure;

With reference now to FIG. 1, an overall system for. wet impact platingof metal parts accordingtto the. present invention may be understood.

The system includes a tumbling barrel '10 which is utilized forindependent parts cleansing, rinsing-and impacting phases of the systemoperation. A conduit.

means 12 provides, through a valve means.l4(which2= for convenience ishereinaftertermed a rinsing valve) selective communication between .asource. of water and the barrel 10.

The water source may be providedinany convenient manner and for purposesof example is illustrated "as being provided by a water storage tank'l6;As hereinafter more fully described, this water storage tank'- 161-alsoserves to provide a source of water forconveyingan. impacting medium forreuse, and to provide a. portion of a water recovery system.

Positioned beneath the tumbling barrel 10. is a .sta-

tionary bin assembly 18; and an overhead hopper :20 is mounted above thetumbling barreLFora purpose which will hereinafter become apparent, thebin assembly 18 is in selectively operable communicationwith a venturieductor 22, the eductor being incommunication with the hopper 20 througha suitable conduit means 24.

A pump 26 is provided for selectively pumping water from the waterstorage tank 16 through the venturi eductor 22 and to the overheadhopper-20. Suitable conduit means, such as thoseindicated at 28 and '30-provide for water flow respectivelyfrom :the. storage. tank 16to thepump 26 and fromthe pump-26'toward the. venturi eductor 22. A suitablevalve means 32, for

.example a simple gate valve, is located in theqconduit':

means 30 for the purpose of selectively controllingthe supplyof waterthrough the venturi eductor.

It will be appreciated thatthe overhead hopper 20 is also in fluidcommunication withthe water storage tank.

16, through gravity flow, by afurther. conduit means-- 34.v Thus, thesupply of water to the hopper 20 'by means of the pump 26 need not, becontrolled toagreat degree, since overflow into the storage tankul6'isper-.

'sions coextensive with the access opening 56 in the 0f thebarrel bygravity (see FIG. 1).

the storage tank 16. A suitable source of water schematically indicatedat 38, supplies make-up water to the storage tank 16 through a conduitmeans 37 communicating with the float valve means 36 in order tomaintain the water level in the storage tank substantially constant. Thewater at the make-up source 38 may be thermostatically controlled bysuitable means 39 so as to ultimately, control the temperature of thewater in the storage tank, and therefore in. the system.

Asindicated .at 40, an overflow conduit means may be provided to placethe water storage tank 16in gravity feed relationship with a waterdisposal area (not shown)., It will beappreciated that the outlet fromthe storagetanklli into. the overflow conduit means 40 is located at ;alevel adjacent the level of the float valve Withparticular-reference toFIGS. 2 and 3, the particular, structure of the tumbling barrel l0,stationary binassembly l8 and overhead hopper 20 may be seen.

The tumbling barrel 10 is provided'with axle and.

bearing assemblies 42 and 44 on opposite ends, thereof. Theseassemblies42 and 44 mount the tumbling barrel 10.,for rotation about a generallyhorizontal axis indi- I cated at 45 andare supported on suitable framemembers 46and 48 stationarily positioned on opposite sides ofthegbarrel. Adjacent oneaxle and bearing assembly 44 'a suitablemotormeans 50 may be provided for revolvingthe barrel 10 at selectedtimes and at a desired adjustable rate. The axle of the other barrelaxle and bearing assembly 42 is hollow and provides communication.between the barrel interior (through means defining .abarrel end openingat 51 located on the axis 45') and. the previously identified conduitmeans 12 in whichv the rinsing-valve 14 is located. It will beappreciated that when water issupplied to the barrel through thatconduit means 12.-from the water storage tank 16' the level ofconnection of the conduit means to the water storage tank is elevatedabove the end opening of the barrel so as to permit water to flow to theinterior Aside opening, indicated at 52, extends longitudinally-ofthebarrel between opposite ends, and except for that opening and thebarrel end-opening, the barrel 10 is otherwise imperforate. The sideopening 52 is sufficiently large to permit easy access to the barrelinteriorduring loading of the metal parts to be plated. A.

trated in FIG. 2 while theperforate door 62 is shown.

inthe schematic diagram of the overall system in FIG. 1. Each of thesedoors and 62 have overall-dimenlarge door 54. Again, suitable means 64may be provided for releasably securingthe smaller doors 60 and 62 inposition. When the small imperforate door 60 is securedin position, thebarrel is substantially water tight. The small perforate door, however,is sized with a mesh sufficient to retain the metal parts and. theimpacting-mediumutilized in the process while permitting aqueoussolutions to pass through the perforations in the door.

It will be appreciated that the door arrangements thus far describedfunction to selectively maintain a peripheral side portion of the barrelor container in a perforate or imperforate condition. Other arrangementsthat function to do the same may be employed if desired.

The previously identified stationary bin assembly 18 is positionedbeneath the barrel between the frame members 46 and 48 supporting thebarrel. Adjacent the top of the bin assembly 18, a stationary screen 66is mounted, with the screen extending entirely across the bin assembly18. It will become apparent that the overall extent of the bin assemblyshould be at least commensurate with the longitudinal extent of the sideopening 52 in the barrel 10 so that the barrel contents may be unloadedinto the bin assembly merely by removing the large door 54 and rotatingthe barrel to a position wherein the side opening 52 overlies the screen66.

The screen 66 is sized with a mesh sufficient to retain the plated partswhile permitting the impacting medium and aqueous solutions to passthrough. Since the bottom of the bin is sloped, as indicated at when theimpacting medium is to be conveyed to the overhead hopper 20 through theutilization of the venturi eductor 22, the impacting medium readilypasses down the sloped bottom. Communication between the lower portionof the bin assembly 18 and the venturi eductor 22 is provided in anysuitable manner as shown at 70. Water supplied through the venturieductor 22 creates a pressure differential which tends to draw thecontents of the bin along with the water to the overhead hopper 20. Fora purpose hereinafter described, the bin assem bly 18 is generally sizedso as to be capable of holding substantially the exact volume of onecharge of the impacting medium utilized in the system.

During hydraulic transfer of this charge of the impacting medium to theoverhead hopper, sufficient turbulence is generated so as to tend tocleanse the impacting medium by removing spent plating material orpromoter chemicals used in the process and which may have adhered to theparticles of the impacting medium. It will be apparent to one skilled inthe art that such turbulence may be created by proper sizing of theconduit means 24 to which the impacting medium is transferred with thesizing taking into account such factors as the hydrostatic headavailable for transfer, the transfer time, etc.

When the impacting medium is transferred to the overhead hopper 20,excess water supplied overflows and passes from the overhead hopper backto the storage tank 16 through the previously identified return conduitmeans 34. The portion of the return conduit means 34 in communicationwith the hopper interior is located within a strainer 71. This strainer71 is sized so as to have a mesh sufficient to retain the impactingmedium in the hopper while permitting overflow water to hydraulicallytransfer suspended particles to the water storage tank 16. The retainedimpacting medium, of course, settles to the bottom of the hopper 20. Atthe hopper bottom, a selectively operable valve 72, or pet cock, isprovided.

As illustrated in FIGS. 2 and 3, the hopper 20 is supported by suitablestrut assemblies 74 mounted on the frame members 46 and 48 so that thepet cock 72 generally centrally located over the tumbling barrel 10.During the portion of the system cycle when the tumbling barrel 10 is tobe supplied with a charge of the impacting medium, the tumbling barrel10 is rotated to a position wherein its access opening 52 is directlybeneath the pet cock 72.

With reference to FIGS. 4 and 5, details of a suitable water storage andsupply system may be seen. The previously identified water storage tank16 is stationarily supported by suitable legs 76. Communicating with thetop of the tank is the previously identified conduit means 34 whichprovide gravity return of overflow fluid'from the hopper 20. Two suchconduit means 34 are illustrated since, in practice, a single waterstorage tank 16 may support several impacting medium handling units(i.e. barrel l0, overhead hopper 20 and bin assembly 18), and thus maycommunicate with the hoppers of each of these assemblies.

The previously identified pump 26 may be a high capacity, open impeller,centrifugal pump which at appropriate times, draws water from thestorage tank 16 through the conduit means 28. Leading from the pump isthe conduit means 30 for supplying water to the venturi eductor 22.Again two such conduit means 30 are illustrated insofar as water may bepumped to the eductors of the several impacting medium handling unitssupported by the single water storage tank 16. The supply of water bymeans of the centrifugal pump 26 may be controlled in any suitablemanner with a conventional line pressure valve (not shown) beingpreferred so that upon manual opening of the gate valve 32 in theconduit means 30 the necessary water will be supplied to the eductor 22.

The condition of the water in the storage tank 16 is generally turbulentfree so that the microscopic particles separated from the impactingmedium and carried into the tank from the overhead hopper 20 tend tosettle out. Periodically, these materials may be manually cleaned fromthe tank. It is readily apparent that access to the water storage tank16 for this purpose may be had through the provision of any suitabledoor or the like.

It will thus be seen that by means of the return conduit means 34 andthe pump 26 both being in communication with the water storage tank, thesystem of the present invention provides for water recovery and reuse,thereby minimizing water expenditure. That water which is supplied tothe tumbling barrel through the conduit means 12 and which is lost assubsequently described, is minimal and is replenished through themake-up water conduit means 37 extending from the make-up water source38.

OPERATION OF THE SYSTEM:

hopper 20 to drop into the barrel 10. At the same time water from theoverhead hopper enters into the barrel. The amount of water usuallyutilized in this portion of the cycle is that sufi'icient to cover thecharge within 9 hqba tlt th e t a m rewatathaajs a ai able from thehopper is needed, this water maybe supplied through manual operation ofthe rinsingvalve 14..

cured in position coextensively with theside opening- 52 of the barrel.This door 54 remainsin that position until the end of the process cycle.

The smaller imperforate door 60 which had been se-,

cured to the larger door during aprevious portionof the cycle, is thenremoved. Cleansing chemicals, which together with waterin the barrelform a cleansing solu: tion, are then added to the barrel .10 throughthe access opening 56 in the large door 54. These. cleansing chemicalsare conventionally employedinimpact platingsystems and need not bedescribed in detail. The small imperforate .door 60 is then securedagain in position and the barrel is rotated about itsgenerallyhorizontal.

may be removed during the processis, however; still present in thebarrel. I I 7 Therefore, after the cleansing phase of the cycle, theimperforate door is replaced by the perforate door 62;

While supplying rinse water to the barrel through the end opening 51upon opening of the rinsing valve 14, the tumbling barrel 10 is againrotated. Duringthis rotation the parts and the impacting medium areretained in the barrel 10 by the perforate door .62 while the rinsingeffluent passes through that door; It will bevapparw ent that thisrinsing cycle, by reason of the rolling rinse,

pump, 26 serves to hydraulically transfer the bin-contents'tothe:overhead hopper 20. During this time is accomplished with a minimum ofwater expenditure. y

The rinsing effluent is thus efficiently separated from the parts to beplated and falls into the stationary bin assembly 18 through thescreen66 at the top of the bin.

At the end of the rinsing phase of the cycle, the perforate door 62 isremoved. At this time, a metalplating powder such as zinc, cadmium, tinorother metal :or

for the plating material and as a mass lubricant so as to- I minimizethe possiblity of damage to the parts through.

abrasion and tangling of the parts.

In'this respect it may be mentioned that agitation of the barrel otherthan by pure rotation about a horizontal axis may be employed. However,this means is preferred insofar as through horizontalrotation the criti-I cality of the time of rotation duringa plating cycle' as well as thecriticality of differences in barrel contents during different cycles,is minimized, thereby decreasingthe-possiblity of deplating by abrasionin the event of variations inthesefaetors.

Atthe end of the plating phase of the cyle, the parts and remainingbarrel content which now need to be separated are dumped out of theplating barrel l0'and into the stationary bin aseembly 18. The screen'66at the top of the bin separates theplated parts from the mass ofimpacting medium and spent plating material and'promoter chemicals'whichpass therethrough. At

this time the parts may be hosed down to hydraulically assist inseparation.

Since the bin is generally sized to accommodate the volume of a singlecharge of impacting medium normally utilized, the rinsingeffluentpreviously accumulated in-thebin is displaced through overflowand is disposed .ofi'Thus the material removed during the cleansingoperation are separated from the impacting medium. If. desired, therinsing effluent may be earlier drained out of the bin through suitablemeans (not shown).-

Upon opening of the gate valve 32 water from the cleansing of spentplating materials and promoter chemicals is accomplished through theturbulence generated as previously discussed.

Overflow water drained out of the overhead hopper 20. through theconduit means 34 carries with it the suspended spent platingmaterial andpromoter chemicals to the water storage tank 16. The overflow strainerpermits this material to pass through while retaining the impactingmedium which settles to the hopper bottom.

In this manner, during each cycle the impacting medium is maintainedrelatively pure so as to lessen the frequency with which impactingmedium rectification is required by reason of attrition.

This time interval is further lengthed through the utilization of twoimpacting medium charges in each tumbling'barrel assembly. Prior totransfer of the impacting medium charge to-the overhead hopper 20, thepreviously transferred charge is placed into the barrel 10. Thus, oneimpactingmedium charge is present in the overhead hopper while the otherremains in either the tumbling barrel 10 or at a later time in the binassembly 7 SUMMARY OF THE ADVANTAGES It may thusbe seen that infollowing the present invention several advantages are realized.Particularly significant is the lessening of the frequency with whichrectification of the impacting medium is required through separating thespent plating materials and promoterchemicals from the system andthrough the use of two impacting medium charges.

Also of importance is the use of a water recoveryand reuse system whichminimizes water expenditure.

Of independent significance is the provision in the system 'for rinsingwhile minimizing the amount of water expenditure required and insuringseparation of therinse water effluent from the parts prior to plating.

Although-the invention has been described with reference toa particularpreferred system, it will be appreciated by those skilled in the artthat additions, modifications, substitutions and deletions other thanthose mentioned may be made without departing from the spirit'or scopeof the invention as defined in" the ap-- pended claims.

' Whatis claimed is:-

' inaatatsae mrr 1. Apparatus for wet plating of metal parts utilizingan impacting medium and plating material, the

a tumbling barrel rotatable about a generally horizontal axis;

a rinsing valve communicating with an end opening of said barrel locatedon said axis;

means defining a side opening extending longitudinally of said barrelbetween opposite ends thereof;

a larger door having a single opening therein and securable to thebarrel coextensively with the side opening thereof and having an accessopening therein;

a smaller perforate door and a smaller imperforate door, eachselectively securable to said larger door at said single openingcoextensively with said access opening thereof;

said perforate door being sized to retain metal parts and the impactingmedium utilized in the system and to permit aqueous solutions to passout of said barrel;

said smaller imperforate door when secured to said larger door, togetherwith said larger door when secured to the barrel, entirely blocking theside opening of said barrel;

a stationary bin positioned beneath said barrel;

a screen mounted adjacent the top of said bin and sized to retain theparts to be plated and to pass a mass of impacting medium and spentplating material;

an overhead hopper positioned above the barrel, the

bottom of the hopper being provided with a selectively operable valve;

a venturi educator communicating with the bottom of said bin inselectively operable relationship;

conduit means providing communication between said venturi eductor andsaid overhead hopper;

a water storage tank;

an overflow strainer in gravity feed communication between the top ofsaid overhead hopper and said water storage tank, said strainer beingsized to pass aqueous solutions and to block passage of impactingmedium;

make-up water supply means communicating with said water storage tankfor maintaining the level of water in said water storage tanksubstantially constant; and,

means for pumping water from said storage tank through said venturieductor and to said overhead hopper.

2. Apparatus for wet plating of metal parts utilizing an impactingmedium and plating material, the apparatus comprising:

a container mounted for at least rotating movement about an axis;

closure means for selectively maintaining a peripheral side portion ofsaid container in a perforate or imperforate condition;

means for supplying liquid to said container during rotation of saidcontainer;

said peripheral portion in its perforate condition being sized to retainthe parts to be plated and the impacting medium while permitting rinsingeffluent to pass through;

bin means positioned beneath said container for collecting a mass ofimpacting medium and spent plating material;

a first remote station; a second station including a source of water;means for hydraulically transferring, utilizing said water from saidsecond station, the contents of said bin means through a conduit to saidfirst remote station while generating sufficient turbulence so as totend to cleanse the transferring medium;

means for hydraulically transferring aqueous solutions, includingsuspended spent plating material, from said first remote station to saidsecond station while retaining said impacting medium at saidrfirststation; and a means for segregating the suspended particles of spentplating material transferred to said second station from the water atthe second station so as to enable reuse of the water from said secondstation for hydraulically tranferring the contents of said bin means tosaid first remote station.

3. Apparatus according to claim 2 wherein:

said container is mounted for at least rotating movement about agenerally horizontal axis.

4. Apparatus for wet plating of metal parts utilizing an impactingmedium and plating material, the apparatus comprising:

a container mounted for at least rotating movement about an axis, saidclosure means for selectively maintaining a portion of said container ina perforate or imperforate condition; means for supplying liquid to saidcontainer during rotation of said container;

said portion in its perforate condition being sized to retain the partsto be plated and the impacting medium while permitting rinsing effluentto pass through;

means adjacent said container for collecting a mass of impacting mediumand spent plating material;

a first remote station;

a second station including a source of water;

means, utilizing said water from said second station, for hydraulicallytransferring said collected mass of material to said first remotestation while generating sufi'rcient turbulence so as to tend to cleansethe impacting medium;

means for hydraulically transferring aqueous solutions, includingsuspended spent plating material, from said first remote station to saidsecond station while retaining said impacting medium at said firststation; and 7 means for segregating the suspended particles of spentplating material transferred to said second station from the water atthe second station so as to enable reuse of the water from said secondstation for hydraulically transferring the collected mass of material tosaid first remote station.

5. Apparatus according to claim 4 wherein:

said container is mounted for at least rotating movement about agenerally horizontal axis.

6. Apparatus according to claim 4 wherein:

said means for collecting comprises bin means positioned beneath saidcontainer and wherein said first mentioned means for hydraulicallytransferring includes conduit means communicating with said bin meansand said first remote station.

7. Apparatus according to claim 6 including:

a screen positioned adjacent the top of said bin means and sized toretain the metal parts and to pass the mass of impacting medium andspent plating material into said bin means.

8. Apparatus according to claim 6 wherein:

said first mentioned means for hydraulically transferring includedventuri eductor means communicating with the bottom of said bin means inselectively operable relationship.

9. Apparatus for wet plating of metal parts utilizing an impactingmedium and plating material, the apparatus comprising:

a container mounted for at least rotating movement about an axis, saidcontainer defining an end opening on said axis;

interchangeable closure means for selectively maintaining a peripheralside portion of said container in a perforate or imperforate condition;

means for supplying liquid to said container, through said end opening,during rotation of said container;

said peripheral portion in its perforate condition being sized to retainthe parts to be plated and the impacting medium while permitting rinsingeffluent to pass through;

stationary bin means positioned beneath said container for collecting amass of impacting medium and spent plating material;

conduit means communicating with said bin means and a first remotestation; and

mans fQL IXQEE lEQllY t9 l th qntsms pr said bin means through saidconduit means to said first remote station while generating sufficientturbulence to tend to cleanse the impacting medium of spent platingmaterial;

means for hydraulically transferring aqueous solutions, includingsuspended spent plating material, from said remote station to a secondstation while retaining said impacting medium at said first station.

10. Apparatus according to claim 9 wherein:

said container is mounted for at least rotating movement about agenerally horizontal axis.

11. Apparatus according to claim 9 including:

a supply of fluid at said second station to provide a fluid to saidmeans for hydraulically transferring the contents of said bin.

12. Apparatus according to claim 9 including:

a screen positioned adjacent the top of said bin and sized to retain themetal parts and to pass the mass of impacting medium and sepnt platingmaterial into said bin.

1. Aparatus for wet plating of metal parts utilizing an impacting mediumand plating material, the apparatus comprising: a tumbling barrelrotatable about a generally horizontal axis; a rinsing valvecommunicating with an end opening of said barrel located on said axis;means defining a side opening extending longitudinally of said barrelbetween opposite ends thereof; a larger door having a single openingtherein and securable to the barrel coextensively with the side openingthereof and having an access opening therein; a smaller perforate doorand a smaller imperforate door, each selectively securable to saidlarger door at said single opening coextensively with said accessopening thereof; said perforate door being sized to retain metal partsand the impacting medium utilized in the system and to permit aqueoussolutions to pass out of said barrel; said smaller imperforate door whensecured to said larger door, together with said larger door when securedto the barrel, entirely blocking the side opening of said barrel; astationary bin positioned beneath said barrel; a screen mounted adjacentthe top of said bin and sized to retain the parts to be plated and topass a mass of impacting medium and spent plating material; an overheadhopper positioned above the barrel, the bottom of the hopper beingprovided with a selectively operable valve; a venturi educatorcommunicating with the bottom of said bin in selectively operablerelationship; conduit means providing communication between said venturieductor and said overhead hopper; a water storage tank; an overflowstrainer in gravity feed communication between the top of said overheadhopper and said water storage tank, said strainer being sized to passaqueous solutions and to block passage of impacting medium; make-upwater supply means communicating with said water storage tank formaintaining the level of water in said water storage tank substantiallyconstant; and, means for pumping water from said storage tank throughsaid venturi eductor and to said overhead hopper.
 2. Apparatus for wetplating of metal parts utilizing an impacting medium and platingmaterial, the apparatus comprising: a container mounted for at leastrotating movement about an axis; closure means for selectivelymaintaining a peripheral side portion of said container in a perforateor imperforate condition; means for supplying liquid to said containerduring rotation of said container; said peripheral portion in itsperforate condition being sized to retain the parts to be plated and theimpacting medium while permitting rinsing effluent to pass through; binmeans positioned beneath said container for collecting a mass ofimpacting medium and spent plating material; a first remote station; asecond station including a source of water; means for hydraulicallytransferring, utilizing said water from said second station, thecontents of said bin means through a conduit to said first remotestation while generating sufficient turbulence so as to tend to cleansethe transferring medium; means for hydraulically transferring aqueoussolutions, including suspended spent plating material, from said firstremote station to said second station while retaining said impactingmedium at said first station; and means for segregating the suspendedparticles of spent plating material transferred to said second stationfrom the water at the second station so as to enable reuse of the waterfrom said second station for hydraulically tranferring the contents ofsaid bin means to said first remote station.
 3. Apparatus according toclaim 2 wherein: said container is mounted for at least rotatingmovement about a generally horizontal axis.
 4. Apparatus for wet platingof metal parts utilizing an impacting medium and plating material, theapparatus comprising: a container mounted for at least rotating movementabout an axis, said closure means for selectively maintaining a portionof said container in a perforate or imperforate condition; means forsupplying liquid to said container during rotation of said container;said portion in its perforate condition being sized to retain the partsto be plated and the impacting medium while permitting rinsing effluentto pass through; means adjacent said container for collecting a mass ofimpacting medium and spent plating material; a first remote station; asecond station including a source of water; means, utilizing said waterfrom said second station, for hydraulically transferring said collectedmass of material to said first remote station while generatingsufficient turbulence so as to tend to cleanse the impacting medium;means for hydraulically transferring aqueous solutions, includingsuspended spent plating material, from said first remote station to saidsecond station while retaining said impacting medium at said firststation; and means for segregating the suspended particles of spentplating material transferred to said second station from the water atthe second station so as to enable reuse of the water from said secondstation for hydraulically transferring the collected mass of material tosaid first remote station.
 5. Apparatus according to claim 4 wherein:said container is mounted for at least rotating movement about agenerally horizontal axis.
 6. Apparatus according to claim 4 wherein:said means for collecting comprises bin means positioned beneath saidcontainer and wherein said first mentioned means for hydraulicallytransferring includes conduit means communicating with said bin meansand said first remote station.
 7. Apparatus according to claim 6including: a screen positioned adjacent the top of said bin means andsized to retain the metal parts and to pass the mass of impacting mediumand spent plating material into said bin means.
 8. Apparatus accordingto claim 6 wherein: said first mentioned means for hydraulicallytransferring included venturi eductor means communicating with thebottom of said bin means in selectively operable relationship. 9.Apparatus for wet plating of metal parts utilizing an impacting mediumand plating material, the apparatus comprising: a container mounted forat least rotating movement about an axis, said container defining an endopening on said axis; interchangeable closure means for selectivelymaintaining a peripheral side portion of said container in a perforateor imperforate condition; means for supplying liquid to said container,through said end opening, during rotation of said container; saidperipheral portion in its perforate condition being sized to retain theparts to be plated and the impacting medium while permitting rinsingeffluent to pass through; stationary bin means positioned beneath saidcontainer for collecting a mass of impacting medium and spent platingmaterial; conduit means communicating with said bin means and a firstremote station; and means for hydrulically transferring the contents ofsaid bin means through said conduit means to said first remote stationwhile generating sufficient turbulence to tend to cleanse the impactingmedium of spent plating material; means for hydraulically transferringaqueous solutions, including suspended spent plating material, from saidremote station to a second station while retaining said impacting mediumat said first station.
 10. Apparatus according to claim 9 wherein: saidcontainer is mounted for at least rotating movement about a generallyhorizontal axis.
 11. Apparatus according to claim 9 including: a supplyof fluid at said second station to provide a fluid to said means forhydraulically transferring the contents of said bin.
 12. Apparatusaccording to claim 9 including: a screen positioned adjacent the top ofsaid bin and sized to retain the metal parts and to pass the mass ofimpacting medium and sepnt plating material into said bin.